[Bug middle-end/98753] -Wfree-nonheap-object on unreachable code with -O0

[boris at kolpackov dot net]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98753

Boris Kolpackov <boris at kolpackov dot net> changed:

           What    |Removed                     |Added
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                 CC|                            |boris at kolpackov dot net

--- Comment #11 from Boris Kolpackov <boris at kolpackov dot net> ---
I believe I am encountering a similar false positive so I will attach the test
cases to this bug (but let me know if I should instead attach them to 54202 or
create a new bug). The attached test.cxx is a cleaned-up original code while
test-simplified.cxx is its further simplified version (thanks to Matthew
Krupcale for coming up with both):

g++ -O1 -c test.cxx 

In member function ‘void small_allocator<T, N, B>::deallocate(void*,
std::size_t) [with T = f()::expr; long unsigned int N = 1; B =
small_allocator_buffer<f()::expr, 1>]’,
    inlined from ‘std::vector<_Tp, _Alloc>::pointer std::vector<_Tp,
_Alloc>::_M_allocate_and_copy(std::vector<_Tp, _Alloc>::size_type,
_ForwardIterator, _ForwardIterator) [with _ForwardIterator = const f()::expr*;
_Tp = f()::expr; _Alloc = small_allocator<f()::expr, 1,
small_allocator_buffer<f()::expr, 1> >]’ at
/home/boris/work/build2/tests/modules/gcc2/gcc-install/include/c++/11.0.0/bits/alloc_traits.h:341:23,
    inlined from ‘void std::vector<_Tp, _Alloc>::reserve(std::vector<_Tp,
_Alloc>::size_type) [with _Tp = f()::expr; _Alloc = small_allocator<f()::expr,
1, small_allocator_buffer<f()::expr, 1> >]’ at
/home/boris/work/build2/tests/modules/gcc2/gcc-install/include/c++/11.0.0/bits/vector.tcc:85:36,
    inlined from ‘void small_vector<T, N>::reserve(std::size_t) [with T =
f()::expr; long unsigned int N = 1]’ at test.cxx:234:26,
    inlined from ‘small_vector<T, N>::small_vector() [with T = f()::expr; long
unsigned int N = 1]’ at test.cxx:163:15,
    inlined from ‘void f()’ at test.cxx:1472:27:
test.cxx:121:27: warning: ‘void operator delete(void*)’ called on unallocated
object ‘exprs’ [-Wfree-nonheap-object]